Three-dimensional Ti3C2Tx-based ordered layered porous wave-absorbing material with good mechanical flexibility
Lightweight foam PEDOT:PSS/Ti3C2Tx/SiO2 composite material prepared by ice template method solves the problem of insufficient absorption performance of traditional electromagnetic protective materials in complex electromagnetic environments, and realizes efficient electromagnetic wave absorption and mechanical flexibility, which is suitable for invisible Aircraft, electromagnetic shielding and communication products.
Patent Information
- Application Number
- CN202411165114.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-23
- Publication Date
- 2025-01-07
AI Technical Summary
Traditional electromagnetic protective materials cannot effectively deal with the diverse and complex electromagnetic environments. Existing materials have shortcomings in electromagnetic shielding and absorption, especially in the fields of wireless communication and detection, new material solutions are urgently needed.
The ice template method was used to prepare light foam PEDOT:PSS/Ti3C2Tx/SiO2 composite material with an orderly layered porous structure. Through etching reaction, ultrasonic dispersion, freeze-drying and other steps, the Ti3C2Tx/SiO2 powder composite material was formed, and the PEDOT:PSS mixes to form a wave absorbing material with good mechanical flexibility.
It achieves excellent absorption performance under different thickness control. The electromagnetic wave reflection loss value is less than -30dB, the electromagnetic wave absorption rate is higher than 99.9%, and the effective absorption bandwidth covers 85% of the X-band, which significantly improves the absorption performance and application. prospect.
Smart Images
Figure CN119264608A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the field of wave absorbing materials, and in particular relates to a light foam PEDOT:PSS / Ti3C2T with an ordered layered porous structure. x Preparation method and microwave absorbing application of SiO2 / SiO2 composite material. Background Art
[0002] Nowadays, as electromagnetic waves gradually dominate the field of wireless communications and detection, while providing convenience to humans, increasingly serious electromagnetic pollution has become a source of pollution that harms human physical and mental health. To solve this problem, electromagnetic protection materials have been recognized as an emerging material in the field of materials science. However, although traditional electromagnetic protection materials have been widely used, they can no longer cope with the current diverse and complex electromagnetic environment. Research on new electromagnetic protection materials is imminent. At present, two-dimensional Ti3C2T x It has shown broad application prospects in the field of electromagnetic shielding and absorption. The ice template method is a method of preparing porous materials using ice crystals as templates. It has the advantages of simple and convenient operation, environmental protection, and rapid prototyping, and has received widespread attention in the field of electromagnetic protection. Summary of the invention
[0003] The technical problem to be solved by the present invention is to provide a lightweight foam PEDOT:PSS / Ti3C2T x Preparation method of / SiO2 composite material and its application in the field of absorbing materials.
[0004] The present invention provides a lightweight foam PEDOT:PSS / Ti3C2T with an ordered layered porous structure x / SiO2 composite material, the absorbing material is Ti3C2T x The absorbing material is composed of SiO2 and PEDOT:PSS, and the content of Ti3C2Tx@SiO2 in the PEDOT:PSS / Ti3C2Tx@SiO2 composite material is 45wt%-55wt%.
[0005] The present invention also provides a lightweight foam PEDOT:PSS / Ti3C2T having an ordered layered porous structure. x A method for preparing a / SiO2 composite material, comprising:
[0006] (1) Ti3AlC2 was mixed with LiF and HCl, etched, washed, and centrifuged to obtain a completely exfoliated Ti3C2T x The colloidal solution was freeze-dried under vacuum to obtain powdery Ti3C2T x Material;
[0007] (2) Ti3C2T in step (1) x The sheet material was dispersed in a mixed solvent of water and anhydrous ethanol, ultrasonicated for 1h-2h, the pH was adjusted to 10-12, and then tetraethyl orthosilicate was added dropwise, stirred for reaction, and centrifuged and freeze-dried after the reaction to obtain Ti3C2T x / SiO2 powder composite materials.
[0008] (3) The Ti3C2T prepared above x The composite material of Ti3C2T / SiO2 powder is evenly dispersed in water and configured into a certain concentration. x / SiO2 uniform aqueous solution;
[0009] (4) Take a certain volume of Ti3C2T in step (3) x / SiO2 uniformly dispersed aqueous solution was mixed with PEDOT:PSS aqueous solution and ultrasonically mixed for 1h-2h to obtain PEDOT:PSS / Ti3C2T x / SiO2 mixed hydrosol.
[0010] (5) PEDOT:PSS / Ti3C2T x The / SiO2 mixed hydrosol was poured into a container of specific size and freeze-dried using the ice template method.
[0011] The mass ratio of LiF to Ti3AlC2 in the step (1) is 1.4-1.8, the molar amount of the HCl solution is 9-12 mol / L, the concentration of LiF in the solution is 40 mg / ml, and the concentration of Ti3AlC2 in the solution is 56 mg / ml-72 mg / ml.
[0012] In the step (1), the etching reaction temperature is 35°C-45°C, the etching reaction time is 24h-48h, the centrifugal speed is 3500-5000r / min, the number of centrifugation is 5-8 times, the freeze-drying temperature is -50°C--72°C, and the freeze-drying time is 120h-168h.
[0013] The concentration of the Ti3C2Tx sheet material added to the mixed solution of ethanol and water in step (2) is 0.2-0.4 mg / ml, wherein the volume ratio of ethanol, aqueous solution and tetraethyl orthosilicate is 120-150:30-45:1, the stirring reaction temperature is room temperature, the stirring reaction time is 18h-24h, the centrifugal speed is 3500-8000r / min, the number of centrifugation is 5-8 times, the freeze drying time is 96-120h, and the freeze drying temperature is -50°C -72℃.
[0014] In step (3), Ti3C2T xThe concentration of the uniform aqueous solution of SiO2 is 15-20 mg / mL.
[0015] In the step (4), PEDOT:PSS / Ti3C2T x Ti3C2T / SiO2 mixed aqueous sol x / SiO2 content is 45wt%-55wt%.
[0016] The solid content of the PEDOT:PSS aqueous solution in step (4) is 1.3%.
[0017] In the step (5), the container is a hollow square polytetrafluoroethylene, the base is a copper plate, the freezing rate is 3-5°C / min, and the freeze-drying temperature is -50°C. -72℃, freeze drying time is 48h-72h.
[0018] The present invention relates to a lightweight foam PEDOT:PSS / Ti3C2T with an ordered layered porous structure. x Preparation method and microwave absorbing application of SiO2 / SiO2 composite material.
[0019] The wave-absorbing material of the present invention has broad application prospects in stealth aircraft, electromagnetic shielding, electromagnetic protection and communication products. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 The light foam PEDOT:PSS / Ti3C2T with ordered layered porous structure prepared in Example x Optical images of / SiO2 composite materials.
[0021] Figure 2 The light foam PEDOT:PSS / Ti3C2T with ordered layered porous structure prepared in Example x / SiO2 composite material cross-sectional SEM image.
[0022] Figure 3 The light foam PEDOT:PSS / Ti3C2T with ordered layered porous structure prepared in Example x Optical image of the compressive resilience test of / SiO2 composite material.
[0023] Figure 4 The light foam PEDOT:PSS / Ti3C2T with ordered layered porous structure prepared in Example x 3D reflection loss plot of / SiO2 composite material as a function of frequency and thickness.
[0024] Figure 5 The light foam PEDOT:PSS / Ti3C2T with ordered layered porous structure prepared in Examplex Two-dimensional reflection loss curve of / SiO2 composite material as a function of frequency and thickness.
[0025] Figure 6 PEDOT:PSS / Ti3C2T prepared in comparative example x Three-dimensional reflection loss curve of / SiO2 composite material as a function of frequency and thickness. DETAILED DESCRIPTION
[0026] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.
[0027] The sources of the drugs required for the embodiments of the present invention are as follows:
[0028] Ti3AlC2, specifications: purity>98%, particles, size ≤75μm, manufacturer: Laizhou Kaixi Ceramic Materials Co., Ltd. Hydrochloric acid (HCl), ammonia (NH3·H2O), tetraethyl orthosilicate (TEOS) and lithium fluoride (LiF), all of analytical grade, manufacturer: China National Pharmaceutical Group Shanghai Reagent Company. PEDOT:PSS, purity: Clevios TM PH1000, manufactured by Germany's Heraeus Group.
[0029] Example 1
[0030] (1) 50 mL of 9M HCl solution was weighed and poured into a polytetrafluoroethylene container. 3.2 g of LiF was weighed and poured into the above hydrochloric acid solution and stirred until completely dissolved. Then 2 g of Ti3AlC2 powder was slowly added to the above mixed solution and stirred at 35°C for 24 h. After the reaction was completed, the supernatant was collected by centrifugal washing with deionized water and placed in a freeze dryer for freeze drying at -75°C and 1 Pa vacuum conditions for 120 h to obtain flaky Ti3C2T x .
[0031] (2) Weigh 30 mg of freeze-dried Ti3C2T x The powder was added into 300 ml of mixed solution (the volume ratio of ethanol to water was 4:1) and ultrasonically dispersed for 45 min until Ti3C2T xThen, 5 ml of ammonia water (27 wt.%) was added to the mixed solution to adjust the pH of the solution to 10. Finally, 1 ml of TEOS solution was added dropwise and stirred at room temperature for 18 h. After the stirring reaction, the solution was washed with deionized water by centrifugation (each centrifugation parameter was 5 min × 8000 rpm), achieving Ti3C2T x The surface was coated with silica nanoparticles and placed in a freeze dryer for 48 hours to prepare Ti3C2T x / SiO2 composite materials.
[0032] (3) Ti3C2T was prepared by ultrasonic method at a concentration of 30 mg / mL x / SiO2 uniformly dispersed aqueous solution, use a pipette to measure the above Ti3C2T x 500 μL of the uniform dispersion of / SiO2 was added with 2 mL of PEDOT:PSS aqueous solution and ultrasonically dispersed for 1 h to prepare PEDOT:PSS / Ti3C2T x / SiO2 mixed hydrosol.
[0033] (4) PEDOT:PSS / Ti3C2T can be prepared by ice template method x / SiO2 foam composite material. The specific operation steps are: x / SiO2 hydrosol was poured into a hollow square polytetrafluoroethylene tube with a copper plate as the base, and liquid nitrogen was used as a cold source to completely freeze the hydrosol at a freezing rate of 3°C / min. The sample was then placed in a freeze dryer and freeze-dried for 48 hours before defrosting to obtain PEDOT:PSS / Ti3C2T x / SiO2 foam composite material.
[0034] like Figure 1 The PEDOT:PSS / Ti3C2T prepared in this example is shown. x Optical image of / SiO2 foam composite material.
[0035] The ordered layered porous PEDOT:PSS / Ti3C2T prepared in this example x The cross-sectional SEM image of the / SiO2 foam composite material is shown in Figure 2 As shown in the figure, it can be seen that the ice template method can make PEDOT:PSS / Ti3C2T x / SiO2 forms an ordered and layer-stacked structure.
[0036] The ordered layered porous PEDOT:PSS / Ti3C2T prepared in this example x Optical images of compressive resilience test of / SiO2 foam composite materials Figure 3 shown.
[0037] The ordered layered porous PEDOT:PSS / Ti3C2T prepared in this example x The microwave absorption performance of / SiO2 foam composite material is shown in the figure Figure 4 , 5 As shown. It can be seen that it achieves excellent absorbing performance under different thickness control (2mm-3.2mm), and its minimum reflection loss value is <-30dB (>99.9% electromagnetic waves are absorbed); when the thickness of the absorber is 2.77mm, it shows the best electromagnetic wave absorption performance, the minimum reflection loss value at 10.95GHz is as high as -58.58dB, the specific intensity value is -21.14dB / mm, and the effective absorption bandwidth is 3.57GHz, covering 85% of the entire X-band. Compared with the foam absorbers reported so far, the foam material synthesized in this experiment has obvious advantages in absorbing performance.
[0038] Example 2
[0039] According to Example 1, in step (3), the Ti3C2T x / SiO2 uniform dispersion 650 μL, the rest is the same as the example, to prepare PEDOT:PSS / Ti3C2T x / SiO2 composite material, which achieved excellent absorbing performance under different thickness control (2mm-2.8mm), and its minimum reflection loss value was <-28dB (>99.9% electromagnetic waves were absorbed); when the thickness of the absorber was 2.63mm, it showed the best electromagnetic wave absorption performance, with the minimum reflection loss value at 9.6GHz as high as -57.5dB, the specific intensity value was -21.86dB / mm, and the effective absorption bandwidth was 3.7GHz, covering 88% of the entire X-band.
[0040] Comparative Example 1
[0041] According to Example 1, in step (3), the Ti3C2T x / SiO2 uniform dispersion 250 μL, the rest is the same as the example, to prepare PEDOT:PSS / Ti3C2T x / SiO2 composite materials, its absorbing properties are as follows Figure 6 As shown, compared with the material performance prepared in Example 1, it exhibits poorer wave absorbing performance.
[0042] Comparative Example 2
[0043] Referring to the literature (Li X, Yin X, Song C, Han M, Xu H, Duan W, Cheng L, Zhang L. Advanced Functional Materials. 2018, 1803938.), the researchers constructed a 3D core MXene. / Graphene foam structure through a sacrificial template method, which has the strongest absorption intensity of -20dB at 3.2mm and an effective absorption bandwidth of 4.2GHz. Although the construction of a MXene-based foam structure can greatly improve the impedance matching of the material, the absorption thickness inevitably increases. In addition, due to the poor mechanical properties of the hollow foam structure, it is easy to collapse in actual applications, resulting in unstable absorption performance.
Claims
1. A three-dimensional Ti3C2T with good mechanical flexibility x The ordered layered porous absorbing material is characterized by: The absorbing material is composed of PEDOT:PSS, Ti3C2T x , SiO2, along with Ti3C2T x @With the increase of SiO2 composite content, the interior of the composite material gradually evolves into an ordered porous structure.
2. The absorbing material according to claim 1, characterized in that: First, you need to x The surface is coated with a layer of SiO2 to synthesize Ti3C2T x / SiO2 powder composite material, and then this Ti3C2T x The Ti3C2T / SiO2 composite powder material is further compounded with PEDOT:PSS. x / SiO2 in the final prepared Ti3C2T x / SiO2 / PEDOT: The content in the PSS composite material is 45wt%-55wt%.
3. A three-dimensional Ti3C2T x A method for preparing an ordered layered porous wave absorbing material, comprising: (1) Ti3AlC2 was mixed with LiF and HCl, etched, washed, and centrifuged to obtain a completely exfoliated Ti3C2T x The colloidal solution was freeze-dried under vacuum to obtain powdery Ti3C2T x Material; (2) Ti3C2T in step (1) x The sheet material was dispersed in a mixed solvent of water and anhydrous ethanol, ultrasonicated for 1h-2h, the pH was adjusted to 10-12, and then tetraethyl orthosilicate was added dropwise, stirred for reaction, and centrifuged and freeze-dried after the reaction to obtain Ti3C2T x / SiO2 powder composite materials. (3) The Ti3C2T prepared above x The composite material of Ti3C2T / SiO2 powder is evenly dispersed in water and configured into a certain concentration. x / SiO2 uniform aqueous solution; (4) Take a certain volume of Ti3C2T in step (3) x / SiO2 uniformly dispersed aqueous solution was mixed with PEDOT:PSS aqueous solution and ultrasonically mixed for 1h-2h to obtain PEDOT:PSS / Ti3C2T x / SiO2 mixed hydrosol. (5) PEDOT:PSS / Ti3C2T x The / SiO2 mixed hydrosol was poured into a container of specific size and freeze-dried using the ice template method.
4. The method according to claim 3, characterized in that: The mass ratio of LiF to Ti3AlC2 in the step (1) is 1.4-1.8, the molar amount of the HCl solution is 9-12 mol / L, the concentration of LiF in the solution is 40 mg / ml, and the concentration of Ti3AlC2 in the solution is 56 mg / ml-72 mg / ml.
5. The method according to claim 3, characterized in that: In the step (1), the etching reaction temperature is 35°C-45°C, the etching reaction time is 24h-48h, the centrifugal speed is 3500-8000r / min, the number of centrifugation is 5-8 times, the freeze-drying temperature is -50°C--72°C, and the freeze-drying time is 120h-168h.
6. The method according to claim 3, characterized in that: The concentration of the Ti3C2Tx sheet material added in the mixed solution of ethanol and water in the step (2) is 0.2-0.4 mg / ml, wherein the volume ratio of ethanol, aqueous solution and tetraethyl orthosilicate is 120-150:30-45:1, the stirring reaction temperature is room temperature, the stirring reaction time is 18h-24h, the centrifugal speed is 3500-5000r / min, the number of centrifugation is 5-8 times, the freeze-drying time is 96-120h, and the freeze-drying temperature is 7. The method according to claim 3, characterized in that: In step (3), Ti3C2T x The concentration of the uniform aqueous solution of SiO2 is 15-20 mg / mL.
8. The method according to claim 3, characterized in that: In the step (4), PEDOT:PSS / Ti3C2T x Ti3C2T / SiO2 mixed aqueous sol x / SiO2 content is 45wt%-55wt%.
9. The method according to claim 3, characterized in that: The solid content of the PEDOT:PSS aqueous solution in step (4) is 1.3%.
10. The method according to claim 3, characterized in that: In the step (5), the container is a hollow square polytetrafluoroethylene, the base is a copper plate, the freezing rate is 3-5°C / min, and the freeze-drying temperature is Freeze drying time is 48h-72h.
11. A PEDOT:PSS / Ti3C2T prepared by the method as claimed in claim 3 x @SiO2 ordered layered lightweight porous foam composites.
12. Use of the absorbing material as claimed in claim 1 in stealth aircraft, electromagnetic shielding, electromagnetic protection and communication products.